1. Field of the Invention
The present invention relates to an optical pick-up driving apparatus, and particularly to an improved optical pick-up apparatus for simplifying the construction of a tracking coil and a focusing coil and providing a more efficient assembling process of the system by using a fine-patterned tracking coil and a fine-patterned focusing coil, which generates a driving force to drive an objective lens.
2. Description of the Conventional Art
Referring to FIGS. 1 and 2, a conventional optical pick-up driving apparatus includes an objective holder 1 which surrounds an objective lens 6 for supporting the objective lens 6, and a printed circuit board (PCB) 5 mounted at one side of the objective holder 1.
Referring to FIG. 4A, a focusing coil 2 is wound around an outer surface of the objective holder 1 and has a certain height.
In addition, as shown in FIGS. 2 and 3A, a plurality of snail-shaped tracking coils 3 are mounted on a left-side surface and a right-side surface of the focusing coil 2, respectively.
The focusing coil 2 and the tracking coil 3 are electrically connected to a predetermined portion of the PCB 5 by an electrical interconnection therebetween.
Meanwhile, a plurality of rectangular insertion grooves 1a, which each extends from the top surface of the objective lens holder 1 through to the bottom surface thereof, are formed within the objective lens holder 1.
In addition, as shown in FIG. 2, a plurality of rectangular-shaped feet 9a are formed, which are inserted into insertion holes 1a of the objective lens holder 1, and yokes 9 each having a permanent magnet 4 (for generating a certain magnetic force in cooperation with the focusing coil 2 and the tracking coil 3) are provided between left-side feet 9a and 9b and between right-side feet 9a and 9b.
The objective lens holder 1, around which the focusing coil 2 having the tracking coils 3 is wound, includes the insertion grooves 1a into which the feet 9a are inserted.
In the drawings, reference numeral 7 denotes a wire spring connected to the objective holder 1.
Because the permanent magnets 4 and the tracking coil 3 of the conventional optical pick-up apparatus are directed to generating a certain magnetic field, when current is supplied to the tracking coil 3, as shown in FIG. 3B, the optical driving-apparatus is driven in the tracking direction in cooperation with the left-side and right-side direction magnetic force based on Fleming's left hand theory (F=B*I*L).
In FIG. 3B, reference character "B" denotes the direction of magnetic field, and reference character "F" denotes the direction of magnetic force.
In addition, when current is applied to the focusing coil 2, the optical pick-up driving apparatus is driven in the upward and downward directions due to the magnetic force based on Fleming's left hand theory (F=B*I*L).
In FIG. 4B, reference character "B" denotes the direction of magnetic field, and reference character "F" denotes the direction of magnetic force.
However, the conventional optical pick-up driving apparatus has disadvantages in that a printed circuit board is additionally necessary for electrically connecting the focusing coil and the tracking coil so as to supply voltage to the focusing coil and the tracking coil. In addition, winding apparatuses for winding the focusing coil around the outer surface of the objective lens holder and for forming the tracking coil, and an assembling apparatus are additionally necessary, thereby increasing manufacturing cost of the product.
Moreover, when manufacturing the focusing coil and tracking coil, manufacturing errors occur since the focusing coil and tracking are manually assembled by mechanical process, so that the performance of the optical pick-up driving apparatus is decreased.